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N Sasano

Publications and source records attributed to N Sasano.

At least 19 recordsLinked to original sources
PubMed1992

Testicular sex cord-stromal lesions: immunohistochemical analysis of cytokeratin, vimentin and steroidogenic enzymes.

We have studied immunolocalization of all steroidogenic enzyme involved in sex steroids biosynthesis, P-450 side chain cleavage (P-450scc), 3 beta hydroxy steroid dehydrogenase (3 beta-HSD), P-450 17 alpha hydroxylase (P-450(17 alpha)) and P-450 aromatase (P-450arom) and that of vimentin and cytokeratin in 14 cases of testicular sex cord-stromal tumours (6 Leydig cell tumours, 5 Sertoli cell tumours, 2 fibromas and 1 granulosa cell tumour) as well as 4 cases of hyperplasia (2 Leydig and 2 Sertoli). Leydig cell tumour expressed all four steroidogenic enzymes examined, indicating that this tumour can synthesize oestrogen from cholesterol. In 2 cases of Sertoli cell tumour, the tumour cells with clear cytoplasm and without Reinke's crystals expressed P-450ssc, 3 beta-HSD and P-450(17 alpha), suggesting the capability of androgen production in these tumour cells. Fibromas and granulosa cell tumour were negative for the enzymes examined. In immunohistochemistry of intermediate filaments, Leydig cell tumours demonstrated only vimentin. Sertoli cells in hyperplasia and non-neoplastic testis expressed only vimentin but Sertoli cell tumours expressed both cytokeratin and vimentin. Cytokeratin immunoreactivity was correlated with morphological epithelial differentiation in Sertoli cell tumour. These findings in testicular Sertoli cell tumour are considered to represent the multiple differentiation capacity of this neoplasm. Immunohistochemical study of steroidogenic enzymes and intermediate filaments provided new insight into neoplastic steroidogenesis and the differentiation capacity of testicular sex cord-stromal neoplasms.

3-Hydroxysteroid Dehydrogenases↗
PubMed1992

De novo expression of aromatase in gastric carcinoma. Light and electron microscopic immunohistochemical and immunoblot study.

We have performed immunohistochemical and immunochemical studies of steroidogenic enzymes involved in estrogen biosynthesis in 30 cases of gastric carcinoma in order to investigate possible in situ production of estradiol (E 2) in carcinoma cells. Positive incidence of immunoreactivity for E 2, testosterone (T), cholesterol side-chain cleavage enzyme (P-450 scc) and aromatase (P-450 arom) were 17/30 (56.7%), 11/30 (36.7%), 3/30 (10.0%) and 23/30 (76.7%), respectively on light microscopy. Estrogen receptor (ER) immunoreactivity was not observed in any of the 30 cases examined. Normal gastric mucosa was negative for P-450 arom and P-450 scc. Examination of serial sections revealed that immunoreactivity of E 2 and P-450 arom were located in the same cells of carcinomatous glands. Immunoelectron microscopy demonstrated that E 2 and P-450 arom were located along the membrane and cisternae of smooth endoplasmic reticulum (sER). Western blot analysis showed one major band of 55 kDa of P-450 arom in the gastric carcinoma tissues examined. Retrospective analysis of immunohistochemistry of E 2 in 108 cases of gastric carcinoma revealed that E 2 positive carcinoma cases were likely to demonstrate better survival rate than negative cases. These results above strongly suggest that E 2 is produced by de novo expressed aromatase in gastric carcinoma cells and is possibly involved in the biology of gastric carcinoma cells.

Aromatase↗
PubMed1992

Primary pigmented nodular adrenocortical disease (PPNAD): immunohistochemical and in situ hybridization analysis of steroidogenic enzymes in eight cases.

Primary pigmented nodular adrenocortical disease (PPNAD) is a rare but an interesting adrenocortical disorder associated with ACTH-independent hypercortisolism. We have studied eight cases of the adrenals with PPNAD by immunohistochemistry of all steroidogenic enzymes involved in cortisol biosynthesis (P-45scc, 3 beta-HSD, P-450c21, P-45017 alpha, and P-45011 beta) and also by performing in situ hybridization of P-45017 alpha in seven cases in order to localize the sites of specific steroidogenesis in this unique disorder. Immunoreactivity of all the enzymes examined was intense in almost all of the cells in adrenocortical nodules, especially the cells with abundant eosinophilic cytoplasm in all the cases examined. The internodular cortex, which demonstrated atrophy in five cases, normal appearance in two cases and hyperplasia in one case, was negative for the enzymes with an exception of 3 beta-HSD. Hybridization signals of P-45017 alpha were condensed over the nodules in in situ hybridization study, suggestive of an increased production of the enzyme itself in cortical cells of the nodules. These results may be consistent with autonomous cortisol production by the nodular cells and indicate that almost all of the cells in the nodules produce cortisol, which can also explain the presence of hypercortisolism despite small sizes of adrenals in PPNAD. Immunoreactivity of steroidogenic enzymes is observed in a small cluster of cortical cells with abundant eosinophilic cytoplasm located at the zona reticularis but not in adjacent non-nodular cortex, which may support an abnormal development of the zona reticularis as a possible pathogenesis of this disorder.

3-Hydroxysteroid Dehydrogenases↗
PubMed1990

Immunohistochemical study of 3 beta-hydroxysteroid dehydrogenase in sex cord-stromal tumors of the ovary.

3 beta-Hydroxysteroid dehydrogenase (3 beta-HSD), which converts pregnenolone to progesterone, was localized immunohistochemically in 18 thecomas, 23 fibromas, 5 granulosa-cell tumors, 5 sclerosing stromal tumors, and 2 steroid-cell tumors. Immunohistochemical study of estrogen, progesterone, and testosterone was also performed in serial sections of thecomas and fibromas. In thecomas, immunoreactivity of 3 beta-HSD was observed only in luteinized theca cells and thecomatous tumor cells with abundant pale to vacuolated cytoplasm but not in spindled tumor cells and thecomatous tumor cells with small to moderate amounts of pale to vacuolated cytoplasm. Immunoreactivity of steroids was not observed in thecomas except for testosterone immunoreactivity in one case. No immunoreactivity of steroids or the enzyme was present in fibromas. No tumor cells were positive for 3 beta-HSD in any of the cases of granulosa-cell tumor examined. Immunoreactivity of 3 beta-HSD was present in cells in steroid-cell tumors and polygonal tumor cells with prominent cytoplasmic vacuoles in two cases of sclerosing stromal tumor. Thus, 3 beta-HSD can be a good immunohistochemical marker of steroidogenesis in functioning ovarian neoplasms.

3-Hydroxysteroid Dehydrogenases↗
PubMed1979

ACTH, beta-LPH and beta-endorphin in pituitary adenomas of the patients with Cushing's disease: activation of beta-LPH conversion to beta-endorphin.

ACTH, beta-lipotropin (beta-LPH) and beta-endorphin concentrations were determined in pituitary adenomas of the patients with Cushing's disease. Immunoreactive ACTH and beta-endorphin were present in high concentrations and essentially equimolar amounts in pituitary adenomas. beta-LPH conversion to beta-endorphin was activated in pituitaries associated with ACTH/beta-LPH producing adenomas. Immunoreactive ACTH and beta-endorphin concentrations were markedly suppressed in the surrounding tissues.

Adenoma↗
PubMed1979

Bronchogenic carcinoma producing ectopic steroid hormones.

A patient with steroid hormones or androgen producing bronchogenic adenocarcinoma was presented. Clinically he had a mediastinal mass and bilateral multiple pulmonary nodules which showed a rapid growth despite cancer chemotherapy. At postmortem examination, radioimmunoassay of the tumor tissue revealed androgen and their precursors. The mitochondria of the tumor cells resembled those of cells in the zona reticularis of the adrenal cortex.

Adult↗
PubMed1979

Myofibroblasts in human breast tumors: an ultrastructural study.

Myofibroblasts were observed in the stroma of breast tumors in all cases examined by electron microscopy; 1 intraductal papillomatosis, 1 papillary carcinoma and 7 infiltrating duct carcinomas. The tubule- or duct-like structure in the tumor tissue were frequently surrounded by myofibroblasts which corresponded to delimiting fibroblasts in the normal breast tissue. In infiltrating duct carcinomas without tubule-like structures, myofibroblasts occurred dispersely in the stroma and they might correspond to fibroblasts in normal connective tissue. A possible role of these myofibroblasts as mesenchymal cells activated in a tumorous condition was discussed.

Breast Neoplasms↗
PubMed1978

[Microdetermination of corticosteroids in adrenocortical zones in various adrenal diseases (author's transl)].

Since the relationship between steroidogenic activity and morphological differentiation is not necessarily clear in the human adrenal cortex, aldosterone (Al), cortisol (F) and corticosterone (b) from the adrenal tissues cut into four small pieces (capsule and glomerulosa, outer fascicular, inner fascicular, and reticular zones) on a cryostat immediately after their removal at surgery were estimated by radioimmunoassay in 15 patients with adrenal diseases (8 primary aldosteronism, 1 idiopathic aldosteronism, 4 Cushing's syndrome and 2 pheochromocytoma) and 8 control subjects with other diseases. A larger amount of Al was contained in the outer fascicular zone than in other zones in control subjects. Al showed a high value of 0.16 approximately 7.40 ng/mg tissue in adenomas of primary aldosteronism and a low value of 0 approximately 0.25 ng/mg tissue in adenomas of Cushing's syndrome. A high value of Al was detected in idiopathic aldosteronism but not in the remaining adrenal of primary aldosteronism. In Cushing's syndrome, F showed a high value of 2.58 approximately 12.3 ng/mg tissue in adenoma and a relatively low level of 0.77 ng/mg tissue in carcinoma. A larger amount of F and B was found in the inner fascicular zone than in other zones in the control subjects. These results indicate that the corticosteroid content in each adrenal zone correlates with the morphological findings.

Adenoma↗
PubMed1978

Evaluation of esophageal dysplasia by cytofluorometric analysis.

In order to grade objectively and characterize dysplastic and precancerous esophageal epithelium its DNA content was measured by cytofluormetric methods and compared to normal and cancerous esophageal epithelium. This yielded the following results. With transition of the esophageal eipthelium from mild dysplasia to severe dysplasia and finally to in situ carcinoma, Feulgen-DNA values showed patterns characteristic of a tetraploid population. They lacked prominent peaks which were usually observed with invasive carcinomas. Dominant near-tetraploid population and definite tetraploid-octoploid populations were characteristic of severe dysplasia or carcinoma. The mean Feulgen-DNA values were significantly larger in severe dysplasia than in the lesser grade of dysplasia as well as the normal epithelium. However, this was not the rule in the full blown carcinomas. It would appear that the esophageal cytophotometric patterns are analogous to those previously observed in the skin and uterine cervix.

Adult↗
PubMed1978

Epithelial dysplasia in cancerous and noncancerous esophagi.

Subserial examinations of the noncancerous esophagus from 86 autopsy materials (male 47, female 39) in Kagoshima Prefecture revealed epithelial dysplasia in 54 instances (63%); 32 males (68%) and 22 females (57%). Higher grades of dysplasia were shown in 17 males (36%) and 3 females (8%). Histologically a formation of the rete ridge-like elongation of basal epithelium was characteristically conspicuous in these materials. Tabacco and alcohol intakes were regarded as promoting factors of dysplasia. Distribution and severity of dysplasia around carcinoma were histologically examined on semiserial blocks in 100 surgical materials under the consideration of preoperative treatment. A coexistence of carcinoma with extensive dysplasia was found in 24 instances and that with multifocal dysplasia in 46. Multicentric in situ carcinoma was found in 19 patients. These in situ carcinomas were frequently surrounded by severe dysplasia and occasionally showed gradual transition to the latter. The lesion of invasive carcinoma sometimes did not show sharp demarcation from the surrounding mucosa, especially in cases of well differentiated squamous cell carcinoma. The results indicate that dysplasia plays a significant role on carcinogenesis of the esophagus as a precursor lesion.

Adult↗
PubMed1978

Autopsy findings in a case of acute paraquat poisoning with extensive cerebral purpura.

An autopsy case of paraquat poisoning in an adult male died on the 6th day of intoxication was presented. Histological and electron microscopic observations demonstrated interstitial pneumonia with distinct interstitial fibrosis and the initial stage of alveolar fibrosis with coexisting edema and hyaline membrane formation. Striking hemorrhagic leukoencephalopathy, i.e. 'purpura cerebri,' was noted throughout the central nervous system involving almost exclusively the white matter. It consisted of focal hemorrhages of various stages accompanied by demyelinating processes of various extent. Globular and/or amorphous proteinaceous materials of uncertain nature were demonstrated in the vascular lumina throughout the brain.

Adult↗
PubMed1976

Polyps and diverticulosis of large bowel in autopsy population of Akita prefecture, compared with Miyagi. High risk for colorectal cancer in Japan.

A necropsy study of polypoid lesions and diverticula of the large bowel in the Japanese prefectures of Akita and Miyagi indicated that adenomatous polyps were more numerous in Akita (30%) than Miyagi (18.3%). They also were larger and showed more severe atypia in Akita. The sigmoid colon and rectum showed the most severe atypia in both prefectures. Hyperplastic polyps and diverticula were very uncommon in both prefectures. These results are discussed in relation to the different levels of risk to colorectal carcinoma in these prefectures and in Japanese migrants to Hawaii.

Adolescent↗
PubMed1976

Histopathological studies on intrahepatic bile ducts in the vicinity of porta hepatis in biliary atresia.

Intrahepatic bile ducts in the vicinity of the porta hepatis were histologically investigated in 9 cases of biliary atresia and the pattern of bile duct was divided into two groups. In the first group, there were a few large bile ducts which had continuity to the extrahepatic bile duct. In the second group, many small bile ducts were histologically observed, but there was no large bile duct at the porta hepatis. This type of abnormal bile ducts was seen in the cases of obliteration of bile ducts at porta hepatis.

Bile Ducts↗
PubMed1976

Comparative studies on dysplasia of esophageal epithelium in four prefectures of Japan (Miyagi, Nara, Wakayama and Aomori) with reference to risk of carcinoma.

Distal two-thirds of the esophagus without macroscopically detectable malignant lesions from a total of 248 autopsy cases were examined for epithelial dysplasia on histological sections from serial blocks. The autopsy specimens had been obtained from Miyagi. Nara and Wakayama prefectures known for high incidence of esophageal carcinoma in Japan, and Aomori prefecture where the incidence of the disease is low. Epithelial dysplasia was classified into mild, moderate, and severe including carcinoma in situ according to the grade of epithelial atypism. Of 248 cases 91 (36.7%) had epithelial dysplasia and 30 (12.1%) had moderate and severe dysplasia. In one of the cases of severe dysplasia, in situ carcinoma was diagnosed. Lesions of dysplasia of the resected specimen were displayed in a diagram for the distribution of the abnormal epithelium. Cases of higher grade dysplasia tended more extensive in area and were slightly dominant in the distal third of the esophagus. Possible relationships of dysplasia with long-standing irritation to the esophagus and with precancerous lesions were discussed.

Adult↗